GUALISH (Libya) - FORCES loyal to Muammar Gaddafi launched a counter-attack on Sunday against rebel advance positions southwest of Tripoli, an AFP correspondent said, as rebels cut off an oil pipeline used to supply the Libyan strongman's forces. Loyalist troops fired half a dozen Grad rockets into the hamlet of Gualish 50km from the capital, and the rebels replied with anti-tank fire as they sought to hold a key gateway to Tripoli they seized on Wednesday. Just hours before the government attack, Nato warplanes bombed positions in the area, the correspondent said. A colonel in the rebel forces said the raid struck near Asablah, 17km from Gualish. In its daily update, the Western military alliance said its planes carried out 48 strike sorties on Saturday, with the focus on the port of Misrata. The rebels on Sunday cut off an oil pipeline they said was used to supply Gaddaf...